Generally, magnetic hard disc drives include transducer heads that read and write data encoded in tangible magnetic storage media. Magnetic flux detected from the surface of the magnetic medium causes rotation of a magnetization vector of a sensing layer or layers within a magnetoresistive (MR) sensor within the transducer head, which in turn causes a change in electrical resistivity of the MR sensor. The change in resistivity of the MR sensor can be detected by passing a current through the MR sensor and measuring the resulting change in voltage across the MR sensor. Related circuitry can convert the measured voltage change information into an appropriate format and manipulate that information to recover the data encoded on the disc.
As improvements in magnetic recording density capabilities are pursued, the dimensions of transducer heads continue to shrink. Typically, transducer heads are formed as a thin film multilayer structure having an MR sensor, among other structures. In some approaches, the thin film multilayer structure includes a synthetic anti-ferromagnet (SAF) to enhance MR sensor stability. However, existing thin film process and structure designs used in forming SAF-based MR sensors present effects that can nevertheless limit MR sensor performance and stability.